Ethyl hexanoate and ethyl butyrate are essential to the flavor compounds in Nongxiangxing baijiu, but low levels of these two esters in upper fermented grains (FG) decreases the quality of upper distilled baijiu, representing the main challenge in Nongxiangxing baijiu production. This paper enhanced fermentation by inoculating functional Clostridium butyricum, Rummeliibacillus suwonensis, and Issatchenkia orientalis strains into upper FG. The results showed that the ethyl butyrate content in the upper FG increased significantly and the content of ethyl hexanoate did improve from the results of many determinations. High-throughput sequencing indicated that the dominant phyla in the FG were Firmicutes, Actinobacteriota, Proteobacteria, Ascomycota, and Basidiomycota. The canonical correspondence analysis (CCA) and person correlation network revealed the relationship between the microbial community, physicochemical environment, and flavor compounds. The temperature, oxygen, and acidity were closely related to the microbial community, while most flavor compounds were positively correlated with Caldicoprobacter, Caproiciproducens, Delftia, Hydrogenispora, Thermoactinomyces, Issatchenkia Bacillus, and Aspergillus. These results helped improve the quality of Nongxiangxing baijiu.

己酸乙酯和丁酸乙酯是浓香型白酒中必不可少的风味物质，但这两种酯在上酢（FG）中的含量低会降低上层蒸馏白酒的质量，这是浓香型白酒生产中的主要挑战。本文通过接种功能性丁酸梭状芽孢杆菌、苏氏鲁姆氏杆菌和东方伊萨氏酵母来强化发酵应变到上 FG。结果表明，从多次测定的结果来看，上层FG中丁酸乙酯含量明显增加，己酸乙酯含量确实有所提高。高通量测序表明，FG 中的优势门是厚壁菌门、放线菌门、变形菌门、子囊菌门和担子菌门。典型对应分析 (CCA) 和人员相关网络揭示了微生物群落、理化环境和风味化合物之间的关系。温度、氧气和酸度与微生物群落密切相关，而大多数风味化合物与Caldicoprobacter、Caproiciproducens、Delftia、Hydrogenispora、Thermoactinomyces、Issatchenkia Bacillus和Aspergillus呈正相关. 这些结果有助于提高浓香型白酒的质量。